标题： 金属中的朗道抗磁响应作为费米面效应 显示英文标题

标题： Landau diamagnetic response in metals as a Fermi surface effect

摘要： 它表明自由电子气和单价金属的朗道抗磁性可以视为费米面效应。 只有靠近费米面的少量电子态具有抗磁活性，而费米面内部的大部分电子态则抗磁惰性。 这种占据电子态的划分是由朗道能级的结构驱动的，可以在倒空间中引入磁通管。 完全填充的磁通管在施加磁场时其能量不会改变，只有靠近费米面的的部分填充磁通管表现出抗磁响应。 利用这种占据电子态的划分，我们推导出稳态抗磁磁化率的一般表达式，为了计算该表达式需要知道费米面的形状及其上的能量梯度。 该方法应用于碱金属，其费米面和能量梯度已通过从头算能带结构计算获得。 发现朗道抗磁磁化率的各向异性取决于外加磁场方向相对于费米面的方向。 这种效应在锂和铯中更为明显，它们的费米面显示出明显的球形变形。 该方法为金属或金属间化合物的朗道抗磁性的从头算计算开辟了一条新途径。 在自由电子气的情况下，该方法也完全描述了抗磁磁化率的振荡德哈斯-范阿尔芬部分。 模型中发现的费米能的小振荡是由于费米面赤道区域的电子重新分布（流入或流出）引起的。 显示英文摘要

摘要： It is demonstrated that the Landau diamagnetism of the free electron gas and a monovalent metal can be considered as a Fermi surface effect. Only relatively small number of electron states close to the Fermi surface are diamagnetically active whereas the majority of the electron states inside the Fermi surface are diamagnetically inert. This partitioning of the occupied electron states is driven by the structure of Landau levels, around which one can introduce magnetic tubes in the reciprocal space. Completely filled magnetic tubes do not change their energy in an applied magnetic field, and only partially occupied magnetic tubes in the neighborhood of the Fermi surface exhibit a diamagnetic response. Using this partitioning of the occupied electron states we derive a general expression for the steady diamagnetic susceptibility, for calculation of which one needs to know the shape of the Fermi surface and the energy gradient on it. The method is applied to alkali metals, whose Fermi surfaces and energy gradients have been obtained from ab initio band structure calculations. It has been found that the Landau diamagnetic susceptibility is anisotropic depending on the direction of the applied magnetic field in respect to the Fermi surface. This effect is more pronounced for Li and Cs, whose Fermi surfaces show a noticeable deformation from the spherical shape. The method opens a new route for ab initio calculations of the Landau diamagnetism of metals or intermetallic compounds. In the case of free electron gas it is shown that this approach also fully describes the oscillatory de Haas - van Alphen part of the diamagnetic susceptibility. Small oscillations of the Fermi energy found in the model are caused by redistribution (inflow or outflow) of electrons from the equatorial region of the Fermi surface.